Short-term effects of wood smoke exposure on the respiratory system among charcoal production workers

Study objectives: We aimed to investigate the short-term respiratory effects of heavy, occupational wood smoke exposure among traditional charcoal production workers. Patients and setting: A total of 22 charcoal workers (mean age, 41 years; 9 current smokers, 5 ex-smokers, and 8 nonsmokers) were studied and compared with a control group of 35 farmers residing in Perama, Rethymnon, Crete. Results: The charcoal workers were exposed to wood smoke for an average of 14 h/d during a mean of 23.7 days required for the burning of kilns. The workers under study mere found to have significantly more cough (odds ratio [OR], 4.8; 95% confidence interval [CI], 1.2 to 19.7), sputum production (OR, 6; 95% CI, 1.4 to 26.5), wheezing (OR, 7.7; 95% CI, 1.4 to 41.5), dyspnea (OR, 28.7; 95% CI, 5.4 to 153), and hemoptysis (OR, 2.7; 95% CI, 0.7 to 55) than the control group. The prevalence of respiratory symptoms such as cough, sputum production, wheezing, and dyspnea in the charcoal workers was significantly elevated during the exposure period (OR, 5.4; 95% GI, 1.1 to 17.7; OR, 5.7; 95% CI, 1 to 31; OR, 9.8; 95% CI, 1 to 88; and OR, 36.7; 95% CI, 1 to 327, respectively). The mean +/- SD percent of predicted values of FVC, FEV1, FEV1/FVC ratio, and forced expiratory flow at 25 to 75% of FVC during the exposure period were significantly lower than those before exposure: 106 +/- 10.8 vs 101 +/- 11.9, p < 0.01; 104 +/- 16 vs 97 +/- 15, p < 0.001; 81 +/- 9 vs 78 +/- 8, p < 0.001; and 95 +/- 27 vs 80 +/- 25, p < 0.01, respectively. The mean +/- SD value of peak expiratory flow at midday and in the evening during the exposure were significantly lower than before: 524 +/- 131 L/min vs 548 +/- 108 L/min, p = 0.03; and 521 +/- 135 L/min vs 547 +/- 131 L/min, p = 0.02, respectively. Conclusions: Our results suggest that wood smoke exposure in charcoal workers is associated with increased respiratory symptoms and decreased pulmonary function. Longitudinal studies are needed to determine potential long-term adverse respiratory effects.